Method for determining the oil content of substances



United States Patent METHOD FOR DETERMINING THE 01L CONTENT OFSUBSTANCES Charles E. Holaday, Arlington, Va., Harry F. Cooke, LittleRock, Ark., Wilbur K. Marble, Stoneville, Miss., and John E. Larrison,Syracuse, N. Y.

No Drawing. Original application May 27, 1955, Serial No. 511,812.Divided and this application March 29, 1956, Serial No. 577,432

. 3 Claims. (Cl. 324 61) (Granted under Title 35, U. S. Code (1952),see. 266) A non-exclusive, irrevocable, royalty-free license in theinvention herein described, for all governmental purposes, throughoutthe world, with the power to grant sublicenses for such purposes, ishereby granted to the Government of the United States of America.

The patent rights for the United States in any invention in the patentto be granted on this application are dedicated to the public.

This invention relates to a process for determining the oil content ofseeds. More particularly, it relates to a process for determining theoil content of cottonseed and other oil-bearing seeds by measuring thedielectric constant of an extract in a solvent whose dielectric constantis known.

If two liquids having different dielectric values are intimately mixed,as by forming a solution of one in the other, the resultant mixture willhave a dielectric value dependent on the relative proportions of the twocomponents. When the dielectirc values of the pure substances and of aplurality of mixtures of known proportions are charted, the proportionsin an unknown mixture may be calculated from the observed dielectricvalue of the mixture.

An object of this invention is to provide method for determining thepercentage of oil in cottonseed by measuring the variations indielectric properties of a number of difierent solutions of oil in asolvent, such as orthodichlorobenzene.

A preferred procedure for preparing an extract of cottonseed formeasuring its oil content in accordance with this invention is asfollows: The first step involves the extraction of oil from 50 grams ofcottonseed in a high speed grinder using 250 grams oforthodichlorobenzene as the extractant. This particular weight ratio ofseed to solvent was found to be efficient and economical for cottonseed. However, for other oil seeds a difierent weight ratio of oil tosolvent may be equally suitable. Before the extracion is started, 30 to40 grams of anhydrous calcium chloride (hydrophilite) are added. Theanhydrous calcium chloride has a desiccating action which preventsmoisture in the seed from becoming absorbed by theoil-orthodichlorobenzene mixture. Although the literature states thatwater is practically insoluble in both oil and orthodichlorobenzene,suflicient absorption takes 2,825,026 latented Feb. 25, 1958 ICC placewhen water is present in the test specimen to materially afiect thedielectric properties of the extract. Thus by using anhydrous calciumchloride as an additive before the extraction, the oil content of anysample of seed may be determined regardless of its natural moisturecontent. Other drying agents may be used, care being taken, however, toavoid the use of materials, such as, aluminum oxide, which will adsorbsome of the oil and thus make any determination erroneous.

In the second step of the procedure the oil-orthodichlorobenzenesolution is separated from the macerated seed. Lint and larger hullparticles are removed by pouring the ground mass of seed through a 40mesh screen which is soldered to the lower inside walls of a metalcylinder. The bottom of the cylinder is attached to a funnel which isinserted into the inlet of an air filter press which utilizes acommercial filter paper as the filtering medium and which serves toremove the fine meat and hull particles. Ground mass remaining on thescreen is first pressed with a wooden plunger to remove as much of theadhering liquid portion as possible. About 5 to 10 pounds of airpressure per square inch is adequate for efiicient filtration of a fluidmixture for determining the oil content with the apparatus. The solutionis now ready for determination of its dielectric properties.

A suitable apparatus for making this determination is disclosed inapplication Ser. No. 511,812, filed May 27, 1955, of which the presentapplication is a division.

By using the above-described process, it is possible to carry out adetermination of the oil content of a sample of cottonseed with greataccuracy in a few minutes. The present oflicial chemical method ofanalysis requires elaborate equipment and a minimum of 12 hours forcompletion.

We claim:

1. A process for determining the oil content of seeds which comprisesadding to a standard weight of seed a standard volume of organic solventfor the oil, said organic solvent having a known dielectric constant,and a desiccant in sufiicient amount to absorb water normally present inthe seed and to prevent absorption of said water by the solution of oil,said desiccant being insoluble in both the oil and the organic solventand being nonabsorbent for both the oil and organic solvent, maceratingthe mixture of seed, organic solvent, and desiccant, separating thesolution of oil in organic solvent from the macerated seed anddesiccant, and measuring the dielectric constant of the solution.

2. The process of claim 1 wherein the desiccant is anhydrous calciumchloride.

3. The process of claim 1 wherein the organic solvent isorthodichlorobenzene.

References Cited in the file of this patent UNITED STATES PATENTS1,076,997 Riddle Oct. 28, 1913 1,610,270 Ehrlich Dec. 14, 1926 2,616,909Carter Nov. 4, 1952 2,617,299 Ennis et a1. Nov. 11, 1952

1. A PROCESS FOR DETERMINING THE OIL CONTENT OF SEEDS WHICH COMPRISESADDING TO A STANDARD WEIGHT OF SEED A STANDARD VOLUME OF ORGANIC SOLVENTFOR THE OIL, SAID ORGANIC SOLVENT HAVING A KNOWING DIELECTRIC CONSTANT,AND A DESICCANT IN SUFFICIENT AMOUNT TO ABSORB WATER NORMALLY PRESENT INTHE SEED AND TO PREVENT ABSORPTION OF SAID WATER BY THE SOLUTION OF OIL,SAID DESICCANT BEING INSOLUBLE IN BOTH THE OIL AND ORGANIC SOLVENT ANDBEING NONABSORBENT FOR BOTH THE OIL AND ORGANIC SOLVENT, MACREATING THEMIXTURE OF SEED, ORGANIC SOLVENT, AND DESICCANT, SEPARATING THE SOLUTIONOF OIL IN ORGANIC SOLVENT FROM THE MACERATED SEED AND DESICCANT, ANDMEASURING THE DIELECTRIC CONSTANT OF THE SOLUTION.